Affectedly polite (7)
I believe the answer is:
genteel
'affectedly polite' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for genteel that I've seen before include "Affectedly refined and upper-crust" , "Exaggeratedly polite" , "Cultured; polite" , ""Refayned"" , "Affectedly refined or respectable" .)